We don't have synonyms for middle dutch yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are middle watch.
(n) :
Collective name for a number of closely related West Germanic dialects (whose ancestor was Old Dutch) which were spoken and written between 1150 and 1500 in the present-day Dutch-speaking area. There was at that time as yet no overarching standard language, but they were all mutually intelligible.
(n) :
Collective name for a number of closely related West Germanic dialects (whose ancestor was Old Dutch) which were spoken and written between 1150 and 1500 in the present-day Dutch-speaking area. There was at that time as yet no overarching standard language, but they were all mutually intelligible.